Ben Cooper knows Chris Moyles better than most. He is a former producer of the maverick DJ and, as BBC Radio 1 head of programmes, was responsible for the day-to-day running of Moyles's breakfast show. Now, as the controller of Radio 1, he is Moyles's boss.

"Chris is a phenomenal broadcaster," he says of the presenter whose capacity to court controversy at the BBC is second only to Jeremy Clarkson's (it would have been third but Jonathan Ross left). Cooper is under pressure to win a younger audience to Radio 1 and 37-year-old Moyles, the station's longest-serving breakfast DJ, has been seized on by critics as the most obvious candidate for the chop.

"He is fine where he is at the moment, he is doing great stuff," says Cooper. "He has got a contract until 2014." But the newly installed controller is equivocal as to whether he will still be presenting the breakfast show by then. "That is a private and confidential issue but he has got a contract with Radio 1. Whether it's breakfast or [elsewhere on] Radio 1 that is for me to know. Chris and I have talked about it and that's something that will stay between me and him."

For a long time, there appeared to be no obvious successor to the motormouth Moyles – drivetime DJ Scott Mills, a year older than him, was unlikely to introduce Radio 1 to a new generation – but now there are at least two waiting in the wings. The morning presenter Fearne Cotton and the afternoon jock Greg James, first spotted in student radio, are the likeliest candidates, both hired by Cooper.

"There is a second XI that is coming up and that gives you options," says Cooper. "I want to keep people guessing because it's an interesting story, it's like a soap opera."

Moyles has generated no shortage of column inches, from the moment 10 years ago when he threatened to "tear the head off" rival DJ Neil Fox and "poo down his neck" to a half-hour rant in 2010 about not being paid on time. "Chris is loved by audiences and hated by journalists," reckons Cooper. Hated? "Yeah, I think so. Especially in this country we love to build people up and knock them down."

Cooper succeeded Andy Parfitt in October and took control at a critical time in Radio 1's 45-year history. Having recovered from a crisis a decade ago when its audience slipped below 10 million (it now has an average weekly reach of 11.7 million), it is under pressure from commercial rivals and the BBC Trust to lower the average age of its audience.

With a target listenership of 15- to 29-year-olds, it was told by the trust in 2009 to refocus on a younger audience. But its average age has since gone up, from 29 to 32, with around 1 million 45- to 54-year-olds tuning into Moyles each week. Cooper says it is an issue that will define his controllership: "The metric of success is going to be the average age."

Some long-running specialist shows have already been axed, including Judge Jules, Gilles Peterson (who will switch to 6 Music), Fabio & Grooverider and Kissy Sell Out. It is a painful process but a necessary one, says Cooper. "Complaints come in saying 'I have been listening to Judge Jules for 10 years and I can't believe you are getting rid of him, I am not listening to Radio 1 again' and you are thinking great, send that off to the trust, that worked."

But a big shift in its audience will require a shakeup of its mainstream, daytime shows. Jo Whiley switched to Radio 2 last year, but presenters such as Vernon Kay, Edith Bowman and Sara Cox are all older than the station's average audience, let alone its target demographic.

"There will be changes over the next few years. It is expected and it will be delivered," promises Cooper. Isn't change required rather sooner? "I'm not Matthew Bannister [the former Radio 1 controller who ousted ageing "Smashie and Nicey" DJs in the mid-1990s]. I am not going to do a sudden night of the long knives." Cooper said it was not a question of presenter's age – "it's not like Logan's Run, everyone over 40 and you're off" – but whether they connected with the audience, such as 54-year-old Tim Westwood: "The average age of his listener is about 23."

One of Radio 1's problems, says Cooper, is the difficulty it has shaking off older listeners who are reluctant to retune to Radio 2 or 6 Music, whom he describes as "trendy adults who just refuse to lose interest in new music". It's a description that might apply to the man himself, with his fondness for turned-up jeans and tweed jackets, suggesting an unlikely mix of Capital Radio (where he worked for two years in the early noughties) and Radio 4.

Engaging company but rarely, if ever, off-message, Cooper appears stumped just twice. Once, when I ask him about his pay, a total package of £162,800, around £50,000 less than Parfitt earned. Evidence, presumably, of BBC belt-tightening. "I am terribly British when it comes to talking about money," he stonewalls. "I just don't want to talk about my salary really. It's out there and up to people to make of it what they will."

And then there were the Radio 1 promotional tie-ups with Coldplay, U2 and Harry Potter, which incurred the wrath of the trust for being too commercial. After a pause longer than one of Lady Gaga's stilettos, Cooper says: "Coldplay and Harry Potter are very relevant to our audiences and we are always trying to innovate in new, creative ways. You have to take risks and sometimes you step over the mark. Hands up."

With one eye already on his legacy, He wants to be remembered for "reinventing radio for the young people of Britain". "Traditional radio for young people is dead in about a generation," he predicts. "We've got to work out what radio looks like on a smartphone, iPad and IPTV."

So, alongside websites and Twitter feeds, there will be pop-up celebrity interviews, live performances and – launching later this month – a live, hour-long online TV show to accompany the Sunday-afternoon top 10 rundown, presented by Reggie Yates. Sounds a bit like Top of the Pops? "I would say this is a visual representation of a chart." Similar, then, just not as catchy.

Cooper also wants to give Radio 1 – facing 20% cuts along with the rest of the BBC as part of Mark Thompson's Delivering Quality First initiative – a new sense of social purpose. He points to its campaigns about alcohol awareness and body image and the Radio 1 Teen Awards held at Wembley last October.

"I was very much taken with that picture of Jamie Oliver walking up to No 10 Downing Street with a petition under his arm about school dinners," he says. "If Radio 1 and 1Xtra could just have that moment, where they are seen doing something good for young people in the UK, that would be amazing."

"I would love Radio 1 to be the unofficial political party of young people in the UK," he adds. "Just celebrate it rather than just being a bunch of hoodies who are doing wrong all the time." But this being the BBC, not too political, presumably.